Sergio Romero

A regular in the Argentine side since his call up to the senior squad in 2009, 26-year-old Sampdoria goalkeeper Sergio Romero is an integral part of Sabella's plans for 2014.

While not among the world's elite goalkeepers, Romero is a more than solid option. However, his unchallenged inclusion does somewhat demonstrate the lack of top Argentine goalkeepers at present.

Romero is a fine shot-stopper, with excellent reflexes and reactions, but can struggle aerially. He is unlikely to make mistakes, though, which makes him the best candidate for inclusion despite his flaws.

Pablo Zabaleta

Manchester City defender, Pablo Zabaleta, has arguably been the best full-back in the Premier League over the past 18 months, and is an important figure for his country as well.

With a combative edge and a wealth of experience, the former Espanyol player offers more to the side than just his talents alone. He is the type of player that can be relied upon under pressure, and that will count for much at forthcoming major tournaments.

Zabaleta has been utilised at right-back under Sabella, having previously featured on the left of defence. He may, though, be required to return to left-back ahead of the World Cup if Bleacher Report's Daniel Edwards is correct with his predictions about the rise of right-back Gino Peruzzi.

Whichever side of the defence he eventually features on, it is certain that he will contribute at both ends of the pitch, and do so with great consistency.

Ezequiel Garay

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With Argentina having settled upon a settled central defensive pairing of Garay and Napoli-owned Federico Fernandez, the Albiceleste have started to benefit from the pair's ever increasing familiarity.

Of the duo, Garay is the better defender. Linked with a move to Manchester United this summer, the Benfica player is technically excellent and a good reader of the game.

Having struggled in a previous spell at Real Madrid, he has kicked on from his initial European struggles to become a fine player since making the move to Lisbon.

If Argentina are to achieve any success at the World Cup, it will need to be built upon a solid defence. A level above the other defensive options, it is clear that Garay will be the key to any such solidity.

Javier Mascherano

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Barcelona star Mascherano is the glue that holds the Albiceleste together at present, offering balance to a side littered with attacking talent.

While the likes of Messi and Aguero are instructed to reap havoc further forward, Mascherano's task is to protect his two centre-backs. It is a role he has played throughout his career, and a role he excels in.

When Sabella took over, Mascherano was relieved of the captaincy in favour of Messi. However, the former Liverpool man has continued to give his all to his country's cause.

At 29, and still improving tactically, he should have a few more years ahead of him at this level.

Fernando Gago

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While Fernando Gago's club career may not be working out quite as planned, with the midfielder currently on loan in his homeland with Velez Sarsfield, he has finally established himself in the national team under Sabella.

It remains to be seen whether Gago can resolve his issues at Valencia this summer, but he should remain in possession of his Argentina place if he can ensure regular, high-level football until the World Cup.

A composed and elegant figure, Gago has struck a good relationship with Mascherano at the base of the midfield, with the pair's contrasting styles proving complementary.

His role is simple: Gago must orchestrate play from the base of the midfield to open up space for his side's attacking players, whilst also remaining focused on his defensive duties.

Angel Di Maria

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Since the arrival of Sabella as manager of the side, Angel di Maria has played an interesting hybrid role in midfield. Not only is he expected to attack down the left as usual, but also to fit into a central midfield three in defence.

Thus far, the experiment has worked well, with Di Maria putting in some excellent performances and helping to ease the creative pressure on Messi ahead of him.

For most countries, a player of Di Maria's talents would be a centrepiece to build around, but he will be forced to take on a supporting role for as long as the Barcelona star is around the side.

That said, if Messi can help take Argentina to major titles in coming years, Di Maria is unlikely to be too worried by taking on a secondary role.

Sergio Aguero

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Manchester City striker Sergio Aguero is another player who could walk into nearly every side worldwide and instantly be heralded as the star. He also, though, finds himself overshadowed by Messi for his country.

Aguero has generally taken a left-sided forward role under Sabella, forming a vibrant front three with Messi and Gonzalo Higuain.

In the role, he is expected to combine principally with the overlapping Di Maria to provide a major threat from the left, and draw attention away from Messi on the other side.

From the position, he has scored three times in his five World Cup qualification outings thus far, and could have had more but for two disallowed goals against Colombia last week.

An important attacking threat, and a team player, Aguero has made himself into one of Sabella's most reliable performers.